In regards to the recent posts about the 6-speed in a dak, here's what we
did to achieve this. Last year for the SEMA show, we built a Quad Cab we
dubbed the 'HR/T'. In it, we used an all stock 4.7L engine. We started
with a 5 speed truck so we didn't have to mess with the automatic's
transmission programming in the computer. We modified the bellhousing,
input shaft & relocated the shifter forward to get the stick in the stock
location. Then a custom drive shaft was made. Point of interest to
everyone, the 3.9L, 5.2L, 5.9L & 4.7L all share the same bellhousing and
input shaft splines, dimensions & clutch hydraulic setup.
As far as the reasoning, if you put a six speed in and look at the gear
ratio spacing, the 6 - speed is a much closer ratio box and will keep the
engine in it's torque peak more easily. A T-56 has two overdrive gears, and
if you're not going for ultimate top speed, you can stiffen up the rear end
gear ratio, getting a better launch, and still not lose any drivability over
the 5-speed. Our HR/T was actually tested prior to it's delivery to us by
Car & Driver magazine. (Sometime in the November/December issue timeframe).
At the time of Motor Trend's Truck Trends magazine testing, the gearing had
not been changed from the factory 3.92 ratio. It's just a blast to driveand
well matched to the high revving 4.7L engine. As far as cruising, it lopes
along in sixth gear and is real easy to speed in. Check the truck out in
this month's issue of Truck Trends and Sport Truck magazine.
-Gary Pinkley
This archive was generated by hypermail 2b29 : Fri Jun 20 2003 - 11:50:45 EDT